251
freshwater spring. The study is based on the assumption that
enhanced biological production occurs due to increased
nutrient inflow caused by terrestrial freshwater supply. Our
results suggest slightly higher plankton abundance outside
the spring and higher settlement in the spring in our biofouling experiments. Fishes, however, as found in the underwater
photos seem to avoid direct contact with the low salinities in
the freshwater wells. In conclusion, due to higher nutrient
concentrations in the freshwater there might be an increased
primary production leading to an increase of primary consumers and in theory also in secondary consumers near the
spring, which have been noted by fishermen around the
world. Further investigations with optimized methodology is
necessary for a better understanding of the subject.
15.3.3 The Urgent Need of Scientific Divers
in Ecological Research on the Example
of Investigations in the Comau Fjord, Chile
Jan Laurenz
1*
, Jürgen Laudien
2
1
Christian-Albrechts-University
Kiel,
Zoological
Institute, Am botanischen Garten 5-9, 24118 Kiel, Germany
2
Alfred Wegener Institute Helmholtz Center for Polar and
Marine Research, Bremerhaven, Germany
*corresponding author: j.laurenz@gmx.de
Technological developments allow performing scientific
work underwater by remotely operated devices and make
dangerous work under excessive pressure unnecessary in
many situations. Nevertheless, some specific research tasks,
in particular concerning ecological issues, can currently not
be performed by any devices available on the market.
Therefore, the work of scientific divers is essential, which
can be demonstrated using the example of the Comau Fjord,
Chile. The structure of the fjord itself, the water depths and
the complexity of the data generation as well as the installation of the experimental setup makes it impossible to operate
a remotely vehicle (ROV). This area is in the focus of several
research projects of the Alfred Wegener Institute,
Bremerhaven. Topics includes population analyses of coldwater corrals, planktonic observations, growths parameters,
colonization, biodiversity, sedimentation and long term monitoring of population diversity. Many tasks concerning these
research projects can only be performed by scientific divers,
highlighting the importance to employ scientific divers.
Examples include pushnet sampling, sediment sampling,
long-term monitoring, underwater drilling, sampling organisms, colonization monitoring, underwater documentation
and measurements of growth parameters. These examples
underline the urgent need of scientific divers in modern
marine science with their ability of interpreting what they
see, the sensitivity of their perception and their ability to
react spontaneously to new and unexpected situations.
Ultimately the human mind and their handicraft skills cannot
be replaced completely by modern technology.
15.3.4 Extracellular Enzymes of Invertebrate
Origin
Imke Böök
1,2*
, Reinhard Saborowski
2
1
University of Bremen, Leobener Straße, NW2, 28359
Bremen, Germany
2
Alfred-Wegener-Institut für Polar und Meeresforschung,
Am Handelshafen 12, 27570 Bremerhaven, Germany
*corresponding author: imke.boeoek@awi.de
Keywords: Biocatalysts, Organic matter, Remineralization,
Nutrient cycles, Fluorophores
Extracellular enzymes are key drivers in the remineralization of organic matter in marine systems. According to the
widespread view such enzymes derive mainly from bacteria.
However, a large number of extracellular enzymes are
released into the water by invertebrates through “sloppy
feeding”, molting, and excretion. These enzymes have the
potential to degrade organic matter and boost subsequent
microbial growth. The aim of this study is, therefore, to
investigate the extracellular enzyme activity in molts and
egesta of different marine invertebrate species with sensitive
fluorometric assays. Visualization of enzymes leaking from
molts and fecal pellets will be achieved by using agarose
plates incubated with fluorogenic substrates. Several
4-Methylumbilliferone (MUF) derivatives will be used to
detect enzymatic activity of selected enzyme classes: MUFPhosphate for phosphatase, MUF-Butyrate for esterase,
MUF-N-acetyl-beta-D-glucosaminide for exochitinase and
MUF-beta-D-Glucoside for glucosidase). Molts and feces
will be placed directly on agar plates and enzymatic activity
will result in a measurable fluorescence signal. First results
results show phosphatase, esterase and glucosidase activity
in fecal pellets of isopods (Idotea baltica and Idotea emarginata). Furthermore, phosphatase activity was verified in
feces of the decapod shrimp (Palaemon sp.) and the gastropods (Littorina littorea). High chitinolytic activity was
found in molts of I. baltica but no chitinolytic activity was
detected in the egesta of the isopods. These results support
the hypothesized important role of extracellular enzymes
from marine invertebrates in remineralization processes.
Further investigation will focus on the quantification and
detailed characterization of these proteins to distinguish
them from microbial enzymes.
Appendices
freshwater spring. The study is based on the assumption that
enhanced biological production occurs due to increased
nutrient inflow caused by terrestrial freshwater supply. Our
results suggest slightly higher plankton abundance outside
the spring and higher settlement in the spring in our biofouling experiments. Fishes, however, as found in the underwater
photos seem to avoid direct contact with the low salinities in
the freshwater wells. In conclusion, due to higher nutrient
concentrations in the freshwater there might be an increased
primary production leading to an increase of primary consumers and in theory also in secondary consumers near the
spring, which have been noted by fishermen around the
world. Further investigations with optimized methodology is
necessary for a better understanding of the subject.
15.3.3 The Urgent Need of Scientific Divers
in Ecological Research on the Example
of Investigations in the Comau Fjord, Chile
Jan Laurenz
1*
, Jürgen Laudien
2
1
Christian-Albrechts-University
Kiel,
Zoological
Institute, Am botanischen Garten 5-9, 24118 Kiel, Germany
2
Alfred Wegener Institute Helmholtz Center for Polar and
Marine Research, Bremerhaven, Germany
*corresponding author: j.laurenz@gmx.de
Technological developments allow performing scientific
work underwater by remotely operated devices and make
dangerous work under excessive pressure unnecessary in
many situations. Nevertheless, some specific research tasks,
in particular concerning ecological issues, can currently not
be performed by any devices available on the market.
Therefore, the work of scientific divers is essential, which
can be demonstrated using the example of the Comau Fjord,
Chile. The structure of the fjord itself, the water depths and
the complexity of the data generation as well as the installation of the experimental setup makes it impossible to operate
a remotely vehicle (ROV). This area is in the focus of several
research projects of the Alfred Wegener Institute,
Bremerhaven. Topics includes population analyses of coldwater corrals, planktonic observations, growths parameters,
colonization, biodiversity, sedimentation and long term monitoring of population diversity. Many tasks concerning these
research projects can only be performed by scientific divers,
highlighting the importance to employ scientific divers.
Examples include pushnet sampling, sediment sampling,
long-term monitoring, underwater drilling, sampling organisms, colonization monitoring, underwater documentation
and measurements of growth parameters. These examples
underline the urgent need of scientific divers in modern
marine science with their ability of interpreting what they
see, the sensitivity of their perception and their ability to
react spontaneously to new and unexpected situations.
Ultimately the human mind and their handicraft skills cannot
be replaced completely by modern technology.
15.3.4 Extracellular Enzymes of Invertebrate
Origin
Imke Böök
1,2*
, Reinhard Saborowski
2
1
University of Bremen, Leobener Straße, NW2, 28359
Bremen, Germany
2
Alfred-Wegener-Institut für Polar und Meeresforschung,
Am Handelshafen 12, 27570 Bremerhaven, Germany
*corresponding author: imke.boeoek@awi.de
Keywords: Biocatalysts, Organic matter, Remineralization,
Nutrient cycles, Fluorophores
Extracellular enzymes are key drivers in the remineralization of organic matter in marine systems. According to the
widespread view such enzymes derive mainly from bacteria.
However, a large number of extracellular enzymes are
released into the water by invertebrates through “sloppy
feeding”, molting, and excretion. These enzymes have the
potential to degrade organic matter and boost subsequent
microbial growth. The aim of this study is, therefore, to
investigate the extracellular enzyme activity in molts and
egesta of different marine invertebrate species with sensitive
fluorometric assays. Visualization of enzymes leaking from
molts and fecal pellets will be achieved by using agarose
plates incubated with fluorogenic substrates. Several
4-Methylumbilliferone (MUF) derivatives will be used to
detect enzymatic activity of selected enzyme classes: MUFPhosphate for phosphatase, MUF-Butyrate for esterase,
MUF-N-acetyl-beta-D-glucosaminide for exochitinase and
MUF-beta-D-Glucoside for glucosidase). Molts and feces
will be placed directly on agar plates and enzymatic activity
will result in a measurable fluorescence signal. First results
results show phosphatase, esterase and glucosidase activity
in fecal pellets of isopods (Idotea baltica and Idotea emarginata). Furthermore, phosphatase activity was verified in
feces of the decapod shrimp (Palaemon sp.) and the gastropods (Littorina littorea). High chitinolytic activity was
found in molts of I. baltica but no chitinolytic activity was
detected in the egesta of the isopods. These results support
the hypothesized important role of extracellular enzymes
from marine invertebrates in remineralization processes.
Further investigation will focus on the quantification and
detailed characterization of these proteins to distinguish
them from microbial enzymes.
Appendices
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